Speed of Sound

Speed of Sound

A sound wave is a pressure disruption that travels through a medium by means of particle-to-particle interaction. As one particle comes to be disrupted, it exerts a force on the next adjacent particle, therefore interrupting that bit from rest and also moving the energy through the tool.

Like any type of wave, the speed of a sound wave describes just how quickly the disturbance is passed from bit to particle.

The velocity of any type of wave is related to its frequency as well as wavelength by v= fλ, where v is the velocity of the wave, f is its frequency, and λ is its wavelength. The speed of sound waves relies on the compressibility and inertia of the medium where they are traveling.

If the medium has elastic modulus E and density  then speed v is given by

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Speed of Sound in Various Media

The velocity of sound varies considerably in different media. The speed of sound in a medium relies on just how quickly vibrational energy can be moved with the medium. Therefore, the derivation of the speed of sound in a medium depends upon the medium and on the state of the medium.

Generally, the formula for the speed of the sound wave in a medium relies on the square root of the restoring force, or the elastic property, divided by the inertial property,


The phase of matter has an incredible effect on the elastic properties of the medium. As a whole, solids have the greatest interactions in between particles, followed by liquids and afterward gases.

For this reason, the longitudinal sound wave travels quicker in solids than they do in liquids than they carry out in gases. Despite the fact that the inertial factor might favor gases, the elastic element has a better impact on the speed (v) of a wave, thus generating this basic pattern:

 V solids>V liquids>V gases

Speed of Sound in Air

The speed of the wave in air depends upon the properties of the air, primarily the temperature, and to a lesser degree, the humidity. The temperature level will certainly impact the strength of the particle communications (an elastic property). At regular air pressure, the temperature dependency of the rate of a sound wave via completely dry air is v = 333m/s.

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This can be found by the equation:



V = 333 m s -1

Atmospheric pressure has no impact at all in an ideal gas approximation. This is because pressure and density both contribute to appear velocity similarly, and in an ideal gas the two results cancel out, leaving just the impact of temperature.

Sound normally travels more gradually with greater altitude, because of reduced temperature.